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"Storm Tracking"
Whether you plan to putrun or ride through weather,
preparation is your best ally
By John Wooldridge
June 2002 Yachting
Outside the protective walls and sturdy pilothouse windows of the
Nordhavn 40, winds whistled through the towing rig, punctuated by
torrential blasts of horizontally driven rain. Waves ranging from
8 to 10 feet in height regularly lifted our stern, while a secondary
set measuring nearly the same rolled in on us from the port side.
Roughly halfway through the early edition of my twice-daily 3:00
to 6"00 watch, I wondered how many new owners of passagemaking
vessels such as this one, which was more than 4,000 miles away from
home and on its way around the world, would eventually have to face
conditions like these. We were about 100 miles from our nearest
harbor of refuge, plowing into a tropical depression that was building
into a late-season Pacific typhoon.
Ironically, the storm had backtracked to a position that placed
our divert destination on the northeast rim of an expanding low
pressure system that would not let us escape on any heading.
I thought about how I would advise owners of full-displacement,
7- to 12- knot cruising vessels to prepare for heavy weather on
long passages.
Whether you're crossing Lake Michigan or heading from Majuro to
Phonpei in Micronesia, as we were, detailed route and weather planning
is a must. To pick the optimum time and route for our voyage based
on seasonal weather patterns, we consulted professional meteorologist
Walt Hack and referenced a copy of Jimmy Cornell's Cruising Routes
of the World. Electronic and backup paper charts helped minimize
the danger of entering new harbors. Twice a day, we downloaded weather
forecasts through a satellite phone to the navigator software that
ran the updates as overlays on laptop-displayed nav charts. An animation
feature showed the potential storm track three days out.
My advice, after surviving this storm, is that you consider staying
put in a known, safe anchorage if the weather looks questionable
in the direction of your destination during the coming three days.
If you have no schedule to keep, settle in and wait the weather
out.
If you must depart, have at least one safe harbor you can divert
to should conditions deteriorate. Few passagemaking boats have the
speed to outrun a system, but most can change course radically.
Heading south or east away from a counterclockwise-spinning low
that is tracking north and west can improve your chances of missing
the storm or buy time if it backtracks.
When you are committed to riding out weather and have the choice,
run down swell. Doing so can offer more comfort and control when
conditions deteriorate. Monitor speed and heading to prevent surfing
down the face of an overtaking wave and plunging the bow into the
wave ahead. Slowing engine speed works in most situations, but be
prepared to stream heavy lines aft for increased drag.
Heading into building waves demands exhaustive attention to course
and direction to prevent accidentally turning beam-to in large seas.
Having a well-maintained hydraulic roll-dampening system will greatly
increase your comfort on either heading, while an auxiliary towed-passive
mechanical system will increase your options, drag and peace of
mind in case of hydraulic failure.
Finally, be prepared to ride out a storm whether you encounter
one or not by never leaving shorthanded.
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